package com.dongjiantong.common.utils;

import org.springframework.core.io.DefaultResourceLoader;
import org.springframework.core.io.Resource;
import org.springframework.core.io.ResourceLoader;

import java.io.IOException;
import java.io.InputStream;
import java.util.NoSuchElementException;
import java.util.Properties;

/**
 * Created by cao on 2017/10/29.
 */
public class PropertiesLoaderUtils {
    //private final static Logger LOGGER = LoggerFactory.getLogger(PropertiesLoaderUtils.class);

    private static ResourceLoader resourceLoader = new DefaultResourceLoader();

    private final Properties properties;

    public PropertiesLoaderUtils(String... resourcesPaths) {
        properties = loadProperties(resourcesPaths);
    }

    public Properties getProperties() {
        return properties;
    }

    /**
     * @Title: getValue
     * @Description: 取出Property，但以System的Property优先,取不到返回空字符串.
     * @param key
     * @Reutrn String
     */
    private String getValue(String key) {
        String systemProperty = System.getProperty(key);
        if (systemProperty != null) {
            return systemProperty;
        }
        if (properties.containsKey(key)) {
            return properties.getProperty(key);
        }
        return "";
    }

    /**
     * @Title: getProperty
     * @Description: 取出String类型的Property，但以System的Property优先,如果都为Null则抛出异常.
     * @param key
     * @Reutrn String
     */
    public String getProperty(String key) {
        String value = getValue(key);
        if (value == null) {
            throw new NoSuchElementException();
        }
        return value;
    }

    /**
     * @Title: getProperty
     * @Description:
     *               取出String类型的Property，但以System的Property优先.如果都为Null则返回Default值.
     * @param key
     * @param defaultValue
     * @Reutrn String
     */
    public String getProperty(String key, String defaultValue) {
        String value = getValue(key);
        return value != null ? value : defaultValue;
    }

    /**
     * @Title: getInteger
     * @Description:
     *               取出Integer类型的Property，但以System的Property优先.如果都为Null或内容错误则抛出异常.
     * @param key
     * @Reutrn Integer
     */
    public Integer getInteger(String key) {
        String value = getValue(key);
        if (value == null) {
            throw new NoSuchElementException();
        }
        return Integer.valueOf(value);
    }

    /**
     * @Title: getInteger
     * @Description:
     *               取出Integer类型的Property，但以System的Property优先.如果都为Null则返回Default值
     *               ，如果内容错误则抛出异常
     * @param key
     * @param defaultValue
     * @Reutrn Integer
     */
    public Integer getInteger(String key, Integer defaultValue) {
        String value = getValue(key);
        return value != null ? Integer.valueOf(value) : defaultValue;
    }

    /**
     * @Title: getDouble
     * @Description: 取出Double类型的Property，但以System的Property优先.如果都为Null或内容错误则抛出异常.
     * @param key
     * @Reutrn Double
     */
    public Double getDouble(String key) {
        String value = getValue(key);
        if (value == null) {
            throw new NoSuchElementException();
        }
        return Double.valueOf(value);
    }

    /**
     * @Title: getDouble
     * @Description:
     *               取出Double类型的Property，但以System的Property优先.如果都为Null则返回Default值，
     *               如果内容错误则抛出异常
     * @param key
     * @param defaultValue
     * @Reutrn Double
     */
    public Double getDouble(String key, Integer defaultValue) {
        String value = getValue(key);
        return value != null ? Double.valueOf(value) : defaultValue;
    }

    /**
     * @Title: getBoolean
     * @Description:
     *               取出Boolean类型的Property，但以System的Property优先.如果都为Null抛出异常,如果内容不是true
     *               /false则返回false.
     * @param key
     * @Reutrn Boolean
     */
    public Boolean getBoolean(String key) {
        String value = getValue(key);
        if (value == null) {
            throw new NoSuchElementException();
        }
        return Boolean.valueOf(value);
    }

    /**
     * @Title: getBoolean
     * @Description:
     *               取出Boolean类型的Property，但以System的Property优先.如果都为Null则返回Default值
     *               ,如果内容不为true/false则返回false.
     * @param key
     * @param defaultValue
     * @Reutrn Boolean
     */
    public Boolean getBoolean(String key, boolean defaultValue) {
        String value = getValue(key);
        return value != null ? Boolean.valueOf(value) : defaultValue;
    }

    /**
     * @Title: loadProperties
     * @Description: 载入多个文件, 文件路径使用Spring Resource格式.
     * @param resourcesPaths
     * @Reutrn Properties
     */
    private Properties loadProperties(String... resourcesPaths) {
        Properties props = new Properties();
        for (String location : resourcesPaths) {
            InputStream is = null;
            try {
                Resource resource = resourceLoader.getResource(location);
                is = resource.getInputStream();
                props.load(is);
            } catch (IOException ex) {
               // LOGGER.info("Could not load properties from path:" + location + ", " + ex.getMessage());
            } finally {
                if (is != null) {
                    try {
                        is.close();
                    } catch (IOException e) {
                    }
                }
            }
        }
        return props;
    }
}
